This invention relates to a reversible pump or motor construction having displacable free-floating rollers which move with respect to drive rollers during operation.
Numerous types of rotary pumps, motors or compressors are known to the art. Some prior art devices utilize an eccentrically mounted rotor within a generally cylindrical housing and have displacable members that move with respect to the rotor and the chamber in which it rotates to either compress a fluid (in the case of a pump) or to transmit fluid pressure to a rotor (in the case of a motor). For example, U.S. Pat. No. 2,465,595 which issued to H. J. Kratzer on Mar. 29, 1949, discloses a positive displacement oscillating roller vane pump having a rotor of a unique shape that is eccentrically mounted with respect to a pump housing in which the rotor rotates. Three displacable roller members are provided, each of which is mounted on arms and controlled by movement of the arms and by the rotor. These rollers, like others in the prior art, are not "free-floating" but instead are supported by arms, spiders or other similar devices. Moreover, many prior art devices, like those shown in U.S. Pat. No. 2,465,595, are not reversible.
In some prior art devices, such as discosed in U.S. Pat. No. 2,036,711 which issued to H. F. Martin on Apr. 7, 1936, an eccentric pump rotor has sliding friction with the inner surface of a pump chamber. The sliding friction in the Martin pump is transmitted through floating rollers, which are confined in radially extending slots in the rotor. A similar rotary engine or pump is disclosed in U.S. Pat. No. 232,017, and a related rotary compressor is disclosed in U.S. Pat. No. 2,562,698. Other apparatus generally relating to the type of pump or motor of the present invention are disclosed in U.S. Pat. Nos. 331,939; 345,885 and 1,317,352.
British Pat. No. 342,561, issued Feb. 5, 1931 to Bever, relates to a rotary pump in which a rotor shaft is eccentrically positioned within a pump casing. A plurality of drive rollers in the casing are supported by discs carried by the shaft so that rotation of the shaft drives the rollers in an annular path about the axis of the shaft. Strips embedded in the drive shaft are biased against the drive rollers to prevent leakage between the shaft and rollers. Each drive roller pushes in front of it an impelling roller than engages and follows the surface of the pump casing. Thus the drive rollers travel along a path concentric with the drive shaft and the impelling rollers travel along a path concentric with the pump casing. As a result, the space between any two impelling rollers increases during part of a revolution through the casing to create a suction, and the space decreases during another part of the revolution to create a pressure.
Italian Pat. No. 426,318, issued Oct. 23, 1947 to Urso, discloses a pump or compressor having a driven cylinder eccentrically located inside a hollow pump cylinder. A first set of driven rollers contacts the driven cylinder and are rotated about their individual axes in response to rotation of the driven cylinder. A second set of driven rollers contacts the wall of the pump cylinder and the first set of rollers so that rotation of the first set of rollers is imparted to the second set of rollers. As the sets of rollers rotate through the space between the driven cylinder and the pump cylinder, the spacing between adjacent rollers increases and decreases, thereby alternately creating a suction force and a pressure force that draws fluid into the pump inlet and forces the fluid out of the pump outlet.
U.S. Pat. No. 2,672,825, issued on Mar. 23, 1954 to Quintilian for a hydraulic pump and motor, discloses a toothed rotor or shell having recesses. Rollers are located parly in the recesses and are contacted by the rotor during operation of the pump or motor.